How do I know that I have missed notifications on Ubuntu 18.04?

When getting notifications while not on the computer, they show up and removed after a few seconds, but I didn't see them.

They are then left in the notification list (super+v or click the clock).

The issue is that the top clock doesn't show any indication that there are missing notification.

Any idea how to show an indication that there pending/missed notifications?

See screenshots:

Closed - no indication:
Closed - no indication

Open - notifications exist:
Open - notifications exist


You can use the Notifications Alert GNOME shell extension. This is how the extension works:

Whenever there is an unread notification (e.g. chat messages), blinks the message in the user's menu with a color chosen by the user.
Notifications Alert GNOME shell extension

The extension also lets you customise the rate of blinking, set up blacklist/whitelist etc.

Another less flashy alternative is provided by the Always Indicator extension. This is how this one works:

Always show the new messages indicator on new messages.
Always Indicator GNOME shell extension

Features:

  1. New message indicator is always shown if there are notifications.
  2. The color of the indicator can be customized.
  3. If 'do not disturb' is active, the icon is displayed in the custom color if there are notifications.

Refer to this to learn more about installing and configuring GNOME extensions: How do I install and manage GNOME Shell extensions?